In a typical high rise building there frequently is found numerous fans, air conditioning systems, dampers, windows, elevators, water and electrical systems and other electrically controlled or controllable apparatus.
In an emergency, such as a fire, the operation of one or more of such apparatuses must frequently be changed to accommodate the type and location of the emergency. For example, in the event of a fire in one or more areas of a building, the building ventilating system should be capable of automatically changing its operation to prevent the incursion of smoke into the noninvolved areas. This is a very important need, for as is well known, smoke, not flame, is one of the greatest causes of loss of life in a fire. At the same time, whatever automatic control is provided, the controlling system must be capable of being overridden to permit manual control of certain of the apparatus by firemen or other emergency personnel.
In the past, the principle technology used for controlling life safety and environmental control systems in a building during an emergency comprised the use of custom built panels containing heavy duty, "oil tight" switches requiring from seven to nine conductors of large size wire for their operation. More often than not, these controls used high voltages for their operation. The use of high voltages necessitated using separate conduit systems from those provided for the rest of the building's life safety systems. The physical size and high voltage nature of the oil tight switches made them impractical for use in graphic annunciator systems, such as those used by firemen to show the status of a building's ventilation and other systems during a fire.
The prior known systems are not readily adaptable to today's modern technology. For example, they are not easily programmed to control apparatus in different ways to accommodate a fire based on the location of the fire in a building.